United States: Florida: Marion County. Ocklawaha River (St. Johns River drainage) north of Eureka and west of Hwy 316 bridge. Collected on northwestern cove of sandy point between boat ramp and river. Floating with Wolffia columbiana and Lemna valdiviana in shade of Salix, Zizania aquatica, Hydrocotyle, and Althernanthera philoxeroides. Fronds floating in contact with water surface, emerald green; sporocarps immature. Lat. 29.3747N Long. -81.9018W.